Hinged teeth for bulldozer moldboards



Nov. 11, 1941. c. E. WILLlAMS ETAL 2,262,415

HINGED TEETH FOR BULLDOZER MOLDBOARDS Filed July 1, 1940 2 Sheets-Sheet 1 22 6 ll I I v /I /"O' [I I 2, a; ll Q l o o I r I o I o o l o 2 INVENTOR Nov. 11, 1941. c. E. WILLIAMS ET AL 2,252,415

HINGED TEETH FOR BULLDOZER MOLDBOARDS Filed July 1, 1940 2 Sheets-Sheet 2 Patented Nov. 11, 1941 a a 2.202.415 a mean Tam roanuunozaa Momnoms Claude E. Williams and Elmer-J. Boy,

1 Seattle, Wash.

Application July 1, 1940, Serial No. 343,442

Our present invention relates to the art of dirt and rock handling equipment of the type normally referred to ,asbulldozers and more particularly the invention relates to hinged teeth for bulldozer moldboards. if I This device consists essentially of pivoting a plurality of steel scarifier teeth to the upper portion of a moldboard of the type used on bulldozers, graders, and the like. These teeth may be joined together so that they operate as a unit in order to insure rigidity against sidesway. They are mounted so that for many uses the bulldozer may be driven ahead with the teeth in the lowered position extending below the lower i cutting edge of the bulldozer moldboard. In such a position they are useful to loosen hard ground, hardpan, rocky material, or for loosening and removingroots and loosening soil in land clearing. However, with our hinged arrangement when it is desired to back up the mold board, in what is known as floating dirt backwardly, which is common in both power driven graders and bulldozers, the teeth, without any attention on the part of the operator, swing outwardly andupwardly so as not to interfere with the floating operation, yet the instant the machine again proceeds forward they bite into the ground and serve their intended purpose. By having the teeth pivoted at a point well up on the moldboard they can be conveniently raised and secured in their raised position. Thus, while they may be quickly put back into service, they will, in their raised position, in no way affect the normal use to which the moldboard is put, whether this be on a bulldozer, grader, or any of the various forms of scrapers using a moldboard scraper.

The use of bulldozers is now being accepted as 'the most practical method in earth moving projects of moving dirt short distances. However, in order that the bulldozer may have a full load on each trip and can quickly acquire the load, it has been necessary in many instances to use various means such as independent scarifying machines, or hand-operated picks, or light blasting to loosen up the firm material so that the blade of the bulldozer can break thesame into a loosened form capable of being transported. This has in the past been an expensive the bulldozer used in its normal manner. This,

even where relatively large areas are being graded, is a very slow, labor. consuming operation and particularly is it expensive becausethe bulldozer itself, which is an expensive piece of equipment, is out of commission during such operation. If it is to be gainfully employed, the bulldozer must of necessity be working constantly, as its depreciation is high and a comparatively large crew is required in its operation and care. Consequently, the various attempts to bolt on teeth, or otherwise fixedly secure them to the moldboard, has not proved satisfactory even where large areas are being worked.

When, however, the area worked is relatively small as in foundation work, excavation of basements, narrow cut work as on roadways and the like, the time required for th changing of teeth is so large a portion of the available working time that such practice is not economically possible, and hand labor tobreak up the material must be employed. It is under such conditions that our present device is particularly useful.

The principal object of our present invention, therefore, is to provide a plurality of scarifier teeth that are hingedly secured to a scraper moidboard and which may be used at will by the operator without loss of time while changing froma dirt handling moldboard to this scarifying ype.

A further object of our invention is to provide scarifier teeth that can be readily swung up out of the way when not in use and which, when in such position, will in no way affect the general usefulness of the moldboard,

Another object of our invention is to provide pivoted teeth which, when the moldboard is backed up, as is necessary when ground is floated, automatically rise out ofthe ground and drag backwardly over the surface-again in no way interfering with the operation of floating, yet being instantly available for loosening material when required.

Another important object of our invention is to provide a tie member across the lower portion of the plurality of teeth, of which there are a varying number of suit conditions. This tie member adds rigidity to the teeth and permits any on tooth that may meet unusual resistance to be mutually supported by the teeth on opposite sides of it. Further, this tie bar is provided with a sharp bend, on each end, adapted to fit over the side closure member of the moldboard so as to give exact positioning of the teeth. This makes it possible for the teeth to be used while the bulldozer is making circular movements, without in any way disarransing the teeth or bending them due to the side movement.

A further object of our invention is to provide means for easily raising the teeth, as a unit, and securing them in the raised position by means that are simple and do not involve auxiliary equipment that would be both expensive and difficult to maintain under service conditions.

Other and more specific objects will be apparent from the following description taken in connection with the accompanying drawings, wherein Figure l is a side elevation of a bulldozer showing the teeth attached thereto and further showing, as a matter of convenience in illustration, a simple means employed to raise the teeth.

Figure 2 is a perspective view showing a bulldozer with our teeth secured thereto in a raised position, with the bulldozer trailing a scraper such as is usedin transporting dirt considerable distances, showing the ease with which the bulldozer can go about its normal functioning without in any way being handicapped by the addition of our equipment.

Figure 3 is a perspective view showing a bulldozer moldboard with our teeth secured in their raised position. a

Figure 4 is a fragmentary view of the front of a bulldozer, showing the moldboard and the teeth secured in their raised position.

Figure 5 is an enlarged perspective view showing the arrangement of our scarifying teeth as they appear in their working position, and illustrating in dashed line a single auxiliary tooth secured to the moldboard and tie bar.

Figure 6 is a fragmentary side elevation, in section, showing the manner in which the moldboard may be used in its normal manner and illustrating how our teeth may be raised out of the way to avoid their interference with the normal functioning of the moldboard.

Figure '7 is a side elevation, in section, showing our teeth in the operation of loosening up firm ground such as hardpan, or rocky ground where the moldboard itself would not be able to bite into and remove the dirt.

Figure 8 is an elevational view in section showing the operation of floating dirt backwardly and illustrating how our teeth swing outwardly and upwardly so as not to interfere with the operation of the moldboard.

Referring to the drawings, throughout which like reference characters indicate like parts, l0 designates, generally, one type of dirt-handling machine known as a bulldozer, with which our scarifier assembly can be most profitably used. It is to be understood, however, that our toothed assembly may be used with any of the blade-typeearth scrapers. However, for simplicity of illustration, we have throughout the accompanying drawings shown our device as secured to a bulldozer. Equipment of this order is normally driven by a track-laying belt as [2 and is provided with a moldboard arrangement It which, through power cylinders and suitable linlrage (all of which is well developed and which form no part of this present invention) is adapted to raise and lower the moldboard assembly l4 and to adequately support it as the moldboard is driven forwardly or rearwardly. The moldboard assembly consists essentially of the moldboard proper I6, to which is preferably secured a high-carbon cutting edge l8 and in order that its dirt-handling capacity may be maintained at a high level it is preferably provided with side, or end, plates as 20 and 2|. In order to stiffen the moldboard, normally, it is flanged at 22 so as to form, in effect, an angle section at its upper margin. These features are present in the conventional bulldozer moldboards as made by various manufacturers.

Our invention consists essentially in providing the toothed assembly, designated generally by the reference character 24, which consists of a plurality of scarifler arms 26 preferably formed of steel and which are made of such a weight and section as to be able to handle, without deformation, the full force that the bulldozer can exert upon them when flrm resistance is encountered. These arms 26 have a point or tooth portion 28, a lower arm portion 29, and each arm is bent as at 30 and is provided with an upper arm portion 32 that is normally substantially straight. The upper end of the arm is pierced to accommodate the pivot bolt 34-there being preferably one such bolt for each of the teeth. To serve as an anchor for pivot bolt 34 we provide, preferably, the two pivot support members 36 and 31 which may be secured to the moldboard in any desired manner; they may be welded thereto if desired, but we find it most convenient to secure them as by bolts 38 so that the whole assembly can be attached to, or detached from,

a moldboard in the field.

At the lowest point where the arms rest against the cutting bar l8 of the moldboard, we provide a tie member 39. This should be, preferably, a steel bar of considerable weight so that it will be adequately strong to distribute the strain from any one arm to those adjacent so that the entire assembly of arms is mutually supported. This member is secured to the arm as by the angle brackets 40 and 4| which may be welded to the arms and welded to the tie bar 39. Each end of the tie bar is bent in a right-angle, directed rearwardly, so that the two lug portions 42 and 53 thus formed extend rearwardly and engage the end plates 20 and M, respectively, and also engage the opposite ends of the cutter bar l8, so that the toothed assembly, which is hingedly supported well up on the moldboard, cannot be deflected sideways due to side strain that occurs when the bulldozer is in operation and greater resistance is met on one side than on the other, or when the bulldozer tends to turn. Inasmuch as bar 39 should be of substantial weight, the lugs 42 and 43 are capable of resisting any side thrust on the arms that the bulldozer itself is capable of placing on the assembly.

When it is desired not to use the toothed assembly we have provided means for easily securing it in its raised position. A most convenient means of accomplishing this is to provide chains as 45 having an elongated link, 46 that may be slipped over the end of the two outside teeth and then led down through bayonet slots ll in the lugs 48 that are, in turn, fixedly secured to the moldboard proper as by being welded thereto. With a reasonable length of chain extending down through opening 41 it is but a moments operation to pull the chain through the opening and then allow the reduced bayonet portion of the slot to engage a link of the chain and hold it in a secure manner.

For use on small bulldozers it will be apparent particularly if only a limited number of teeth are employed, as we have illustrated in our drawings, that it is relatively easy for one or two men to raise the toothed assembly as desired and to lower the same. However, when used with the larger equipment or where conditions indicate that a greater number of teeth should be employed, we find it most convenient to employ an auxiliary raising means. The simplest that we have, as yet, been able to devise, is to provide a steel cable, or chain, it having an elongated link at BI and a hook at 52. With this arrangement it will be apparent, it is believed, particularly from a study of Figure 1, that hook 52 may be looped over one of the traction lugs on belt i2, passed over the angled portion 22 of the moldboard and down to the link II which may be engaged over one arm. The operator may then, by backing up slightly with his tractor tread belts, raise the toothed assembly. When it is in its upper position, the locking chain assembly 45 may be used to secure it in its raised position. To put the arms back in service, the strain can be taken by cable 50 in the same manner so that chains 45 can be released from the bayonet slot and then, by moving the machine forward, the operator can lower the toothed assembly easily to the ground.

Our present arrangement permits auxiliary teeth, for use in land clearing, to be easily attached. These auxiliary teeth 26a are similar to the scariiier arms 26 having the same pivot bolt 34 and the pivot support members 38 and 31 which are attached to the mold board in the same manner as by bolts 38. There are, preferably, angles similar to Q and ll welded to the auxiliary arm which when the teeth lie on the tie bar 39 can be temporarily fastened to the tie bar by suitable securing means. I

Any one of the auxiliary arms can be used as a single arm. should the hinged assembly be detached. The auxiliary arm may be fastened between the angle 36 and 31 on themoldboard with one of the same bolts that are used to hold the hinged assembly. This permits the angles that are welded to the auxiliary arm to lie on the cutting bar of the bulldozer where it can be securely fastened by bolts or latches. This is often very helpful in any emergency where a small corner or area ofhardpan is encountered.

A study of ourdrawings, it is believed, will illustrate the construction and the general manner of using our equipment. In Figures 8, 7, and 8 we have shown three dliferent positions for our toothed assembly. In Figure 6 we show the teeth as raised, and held in the raised position. with the moldboard picking up a load of dirt. In this operation the teeth are not used and, when in their raised position they in no way interfere with the normal functioning of the bulldozer. When, however, hardpan, stony or rooted ground is encountered, the teeth are lowered-and operated as illustrated in Figure 7 wherein the teeth extending well below the cutting bar It bite into the ground at I! and loosen the same so that the bulldozer may be effectively employed.

In Figure 8 we. show what is known as "floating dirt that has been otherwise collected, over which the moldboard is placed and the whole machine moved to the rear and the dirt thus spread out evenly. In this operation it will be noted that the teeth rise out of the dirt and again in no way interfere with the operation.

The foregoing description and the accompanying drawings are believed to clearly disclose a preferred embodiment of our invention but it will be understood that this disclosure is merely illustrative and that such changes in the invention may be made as are fairly within the scope and spirit of the following claims.

We claim:

1. A toothed bly for earth-moving blades rality of pivot comprising-a plurality of scarifler arms having scariiler teeth at their outer extremities, a plurality of pivot support members on the face of an earth-moving blade, said arms being pivotally attached to said pivot support members, a tie bar secured to said arms and cooperable with the lower edge of the earth-moving blade, a rearwardly bent lug on each end of said tie-bar cooperable with the ends of the earth-moving blade to resist transverse movement of the toothed assembly with relation to said blade.

2. A toothed assembly for earth-moving blades comprising a plurality of scarifier arms having scarifler teeth at their outer extremities, a plurality of pivot support members on the face of an earth-moving blade, said arms being pivotally attached to said pivot support members, a tiebar secured to said arms and cooperable with the lower edge of the earth-moving blade, a rearwardly bent lug on each end of the toothed assembly cooperable with the ends of the earthmoving blade to resist transverse movement of the toothed assembly with relation to said blade.

3. A toothed assembly for earth-moving blades comprising a plurality of scariiier arms having scaritler teeth at their outer extremities, a plusupport members on the face of an earth-moving blade, said arms being pivotally attached to said pivot support members, a tie-bar secured to said arms and cooperable with the lower edge of the earth-moving blade, means on each end of the toothed assembly cooperable with the ends of the earth-moving blade to resist transverse movement of the toothed assembly with relation to said blade.

4. A scarifier device for earth-moving blades comprising a tie-bar cooperable with the lower edge of an earth-moving blade, a plurality of scarifier arms each having a scarifier tooth at its outer extremity, said arms being secured to said tie-bar spaced apart from each other, means for pivotally securing said scariiler teeth to the earth-moving blade so that the lower tooth extremity of each scarifler arm extends below the lower edge of the earth-moving blade, and means for resisting transverse movement of said scarifler device with relation to said earthmoving blades.

5. A toothed assembly for earth-moving blades comprising a plurality of scariiier arms having scariiier teeth-at their outer extremities. a tiebar securing said arms together in spaced-apart relationship to each other and cooperable with the lower edge of the earth-moving blade, means on said toothed assembly cooperable with the earth-moving blade to resist transverse movement of the toothed assembly with relation to said blade, said assembly being pivotally attached in its upper portion to an upper portion of the earth-moving blade.

6. A scarifier device for earth-moving blades comprising a tie-bar cooperable with the lower edge of an earth-moving blade, a plurality of scarliier arms each having a scarifier tooth at its outer extremity, said arms being secured to said tie bar spaced apart from each other, means for pivotally securing said scariner device to the earth-moving blade, and means for resisting transverse movement of said scariner device with relation to said earth-moving blades. 

